Rutter and Wilbanks Corp. plans to drill a second sidetrack from its Ahtna 1-19 well next month, near Glennallen in Alaska’s undeveloped Copper River basin, Bill Rutter Jr. told Petroleum News July 16.
“We hope to sign a contract with Nabors” for a rig, Rutter said.
In June the company discovered gas in its first sidetrack from the Ahtna well. But the well was also producing water at the rate of about a barrel per minute, Rutter said. And it was impossible to tell whether the water was coming from the gas reservoir or from higher up in the well.
“We know water was coming before we hit the gas,” Rutter said. “After we hit the gas we’re not sure whether there was any additional water or not.”
So, the company has plugged the well and now plans to case a second sidetrack, to isolate the pay zone and thus prove how much water is coming from the gas reservoir. Excessive water production would render the well uneconomic.
The second sidetrack would target a sand in the lower part of the upper Nelchina formation, Rutter said. If water production from that sand is excessive, the company will probably plug the well. If, on the other hand, water production proves to be low, drilling would continue into the lower Nelchina sands.
There definitely is gas at high pressure in the Nelchina, because gas reaching the surface from the June discovery is overcoming 4,000 pounds of pressure from well fluids and the back pressure used to keep the water circulating, Rutter said.