Gasco Energy Inc., Denver, (NYSE Alternext US: GSX) spudded two gross wells (0.75 net) and reached total depth (TD) on three gross wells (1.66 net) during the fourth quarter on its Riverbend project in Utah's Uinta Basin.

All of the wells during the quarter were drilled into the Upper Mancos shale. Gasco now has 17 wells, not including the original partial Mancos penetration, that have reached total depth within the Mancos shale and two additional wells that have tested the Dakota formation.

Gasco has conducted initial completion operations on five gross wells (2.25 net) and re-entered one gross well (0.93 net) to complete behind-pipe pay zones. Gasco has now completed 18 wells in the Mancos shale interval since it began targeting the Mancos in mid-2007. There are currently two Mancos shale wells awaiting initial completion.

The GCS #23-16 (25% working interest, Gasco operated), a Dakota and full Mancos shale interval test, reached total depth of 16,610 feet on June 13. The well is completed in the Morrison Formation with one frac job and in the Dakota formation with three frac jobs.

The coiled tubing unit became stuck while drilling out the frac plug. Subsequent fishing operations recovered all of the string except the bottom-hole assembly. The current plan is to flow the well through the fish in the hole and obtain a gas-flow rate before moving up the hole to complete the Mancos through the Kenilworth member of the Blackhawk Formation.

At year-end 2008, Gasco operated 129 gross wells and the company has an inventory of 30 operated wells with up-hole recompletion potential and two wells awaiting initial completion activities.
Gasco president and chief executive Mark Erickson says, “With respect to the GC #23-16, we are disappointed that we are unable to fully test the Morrison and Dakota due to mechanical issues. We found an over-pressured gas-charged reservoir. The flow test results are difficult to interpret due to the mechanical issues, but the test did not indicate that economic quantities of hydrocarbons can be produced from this well in the Dakota and Morrison intervals. It is unclear to us which part of the completion the production is coming from due to the junk in the hole.”

Gas has oil and gas assets in the Rockies region, primarily in the Uinta Basin of northeastern Utah.