According to the company, the northern and southern ends of the field into the processing plant have been tied-in with the connection of the ASD 3-17 and 6-17 wells.

Marion said it was necessary to shut-in the field as tie-ins were made and safety tests carried out.

"Shut-in periods will also occur from time to time as the ASD 3-17 and 6-17 wells, together with the Ridge Runner wells, are all brought on stream and production is increased to its full capacity," the company added.

Marion believes the two ASD wells exhibit the characteristics of the original wells drilled in the 1950s and produced more than 137 billion cubic feet of gas at an average of over 8Bcf per well.

"The ASD wells appear very similar in character to the earlier wells drilled and are expected to perform in a similar manner," the company said.

The commissioning operations of the ASD wells are expected to take 4-8 weeks to complete.