Horizontal drilling has been proven effective in natural gas fields where pockets of gas is trapped in narrow shale formations. Of course there are a number of additional energy related substances being harvested in the process to varying degrees depending on location. On the Alaska North Slope where there is permafrost in the ground solid on the surface in the winter but kind of soupy in the summer due to melting of the top 4-6 feet of the surface they create workpads rising over the surrounding area by bringing in a lot of gravel and thereafter locate the drills there. Drilling is then done at various angles from the site depending on the location to be reached.
I am not aware of horizontal drilling done there by the end of the nineteen eighties when I left. There is a lot of natural gas easy to access but difficult to transport thus I suspect that until the transport issue is solved horizontal drilling is a moot point.
"difficult to transport" is kind of an understatement.
There is no pipeline so there would need to be a very long and expensive pipeline constructed. It has been proposed from time to time but nothing ever happened.
As BPT holders you should hope such a pipeline never gets built. BPT would get no royalties from NG production and currently the NG produced is pumped back in to maintain resevoir pressure. If the NG were piped out, pressure would decline meaning BPT production and distributions would likely drop.
Not sure whether they need to for the type of resevoir in Prudhoe Bay (I'm not an engineer so that's a guess).
But it's not really the amount of 'reserves' which is the important factor for this trust. There are reserves to allow economic production for decades into the future. The potential issues are insufficient pressure in the Transalaska pipeline to keep it operating (however recent tax reductions in Alaska may encourage increased drilling which may alleviate that concern) and the big issue of the escalation of chargeable costs starting in 2018 as built into the trust structure. The latter may mean that although there are decades left of reserves that could and will be produced, the trust may not be able to make distributions within less than a decade (depending on oil prices). It's the trust structure that is the big risk here, not the amount of reserves.