Oct. 5--A test of new technology to produce heavy oil on the North Slope has had encouraging results, BP Exploration (Alaska) Inc. said Sept. 29.

"This is really good news because this is a giant resource, with about 20 billion barrels of oil physically in the reservoir. We think the time is right to go after it," said BP spokesman Steve Rinehart.

Based on the success of the test, BP will drill three more test production wells in the coming weeks and will build a processing and test facility this winter that will be installed next summer at the Milne Point field.

Four more test production wells may be drilled the following year.

Meanwhile, ConocoPhillips is preparing to test another technique for producing the cold, thick oil by warming the oil underground in a test well drilled in the Kuparuk River field, said Bowen Roberts, ConocoPhillips' manager for the project.

Heavy oil poses major technical challenges and is very costly to produce, but both companies believe there is good potential for production that can be sustained over long periods to help offset the decline in conventional light oil.

Heavy oil must be mixed with conventional crude to flow through the trans-Alaska oil pipeline, however.

Most of the estimated 20 billion barrels of heavy oil on the North Slope is in the Ugnu deposit, a shallow reservoir overlying the Milne Point, Prudhoe Bay and Kuparuk River fields.

As it sits in the rocks, some heavy oil will barely flow and much of it won't move at all. It has a consistency that ranges between maple syrup and shoe polish.

The companies have to do something to make it move.

BP's approach, in its test project at Milne Point, is a technology called cold heavy oil with sand production, or CHOPS. It is a procedure being used to produce heavy oil in Alberta by Canadian oil producer Husky Oil Ltd. In one project there Husky is producing 150,000 barrels per day, according to Eric West, BP's manager in charge of the heavy oil project.

Heavy oil is being produced in California, Venezuela and Alberta, and the companies operating in Alaska are taking advantage of lessons learned in those places. Venezuela's heavy oil is a little lighter than Alaska's, and Alberta has oil that is heavier than in Alaska.

ConocoPhillips is taking a different tack in the Kuparuk field, using an electric heater placed down in the well to heat the heavy oil so that it will flow, said Bowen Roberts, coordinator on the project.

ConocoPhillips drilled an Ugnu test production well in 1998, in the southeast part of the Kuparuk field, and has been testing different production procedures intermittently over several years, Bowen said. The most recent, done last year, involved injection of diesel down the well to warm the oil.