Alaska’s Division of Oil and Gas has authorized Arctic Slope Regional Corp. to make gravel improvements to the 7-11-12 pad in the Prudhoe Bay unit on the North Slope, in preparation for a program of methane hydrate production testing. On May 19 ASRC Consulting and Environmental Services LLC filed an application with the division for approval of the testing program. The gravel improvements at the 7-11-12 pad are one component of this program. The division has yet to issue any decisions on the remainder of ASRC’s application, and the application itself is not yet publicly available.
However, the 7-11-12 pad was the site of a successful methane hydrate test well, completed in early 2019. The drilling came as part of a research project conducted by a partnership between the U.S. Department of Energy’s National Energy Technology Laboratory; Japan Oil, Gas and Metals National Corp.; the U.S. Geological Survey and Petrotechnical Resources of Alaska. BP, then operator of the Prudhoe Bay unit, oversaw the drilling. ASRC is also involved in the program.
The division says it understands that ASRC is finalizing an agreement with Hilcorp North Slope, now Prudhoe Bay operator, for conducting a methane hydrate test program within the impacted lease area.
Further drilling planned
After the test well was completed in 2019, subsequent permit applications filed with the division by ASRC indicated an intent to drill further wells in the winter of 2021-22, to be followed by a hydrate production test program in 2021 or 2022. The concept was to drill two additional wells: a methane hydrate production well and a monitoring well, for determining the subsurface response to the production. The well that had already been drilled would become a second monitoring well.
According to information published by NETL, the test well completed in early 2019 penetrated two highly saturated methane hydrate reservoirs. The deeper of these reservoirs appeared particularly suitable for production testing, while the shallower reservoir could provide additional research opportunities.
And in April 2019 ASRC Energy Services Alaska applied to Alaska’s Division of Mining, Land and Water for the use of gravel pads across the region between the Colville and Canning Rivers for subsurface temperature monitoring in connection with the methane hydrate test program.
However, no further drilling for the test program has happened. Although the research partnership has not issued any status report on the program, the drilling plans may have been impacted by the hiatus in North Slope drilling as a consequence of the COVID pandemic.
A huge potential resource
Methane hydrate is a solid in which molecules of methane, the primary component of natural gas, are concentrated inside a lattice of water molecules. Huge quantities of the material, which remains stable within a certain range of relatively high pressures and low temperatures, are known to exist around the base of the permafrost under the North Slope. Gas can be released from hydrates through some combination of elevating the temperature or reducing the pressure of the hydrate resource. Although there have been demonstrations of short-term hydrate production, no one has yet conducted a sustained production test of the type envisaged on the North Slope.
There is international interest in the feasibility of producing natural gas from hydrates - hence the North Slope project. Assuming that production is technically possible, the commercial practicalities of producing gas in this manner on the North Slope would also depend on numerous factors, including some means of shipping the gas to market or of using the gas in some other way.
- ALAN BAILEY
