In addition to hydraulic fracturing technology, horizontal drilling (also called directional drilling) has made it possible for producers to access more of the oil in shale formations while disturbing less land on the surface.
To do this, companies use state of the art technology to drill down thousands of feet to what is called the “kick-off point.” At this point, directional drillers will begin drilling at a very gradual angle until the drill bit and steel pipe land horizontally in the middle Bakken formation. Once in the middle Bakken formation, the driller will drill out an additional two miles through the target zone, allowing producers to pull oil from thousands of feet of a single wellbore.
In the past, vertical drilling allowed for only one well per well pad placed as often as every 40 acres, impacting up to 10 or 12 percent of the surface area. Today, advances in horizontal drilling allows a single well pad to hold multiple wells, allowing wells to share access roads and equipment, which significantly reduces the land needed for each well. These well pads are located along planned “energy corridors,” which are existing roadways or section lines along one end of spacing units. Creating an energy corridor allows for a majority of the well site traffic to be confined to one road, reducing impacts and leaving more than four square miles in between it and the next energy corridor, which may be situated four miles away. This leaves more than four miles in between each energy corridor undisturbed and available for agricultural, grazing, habitat or human use.
The benefits are significant. Because horizontal drilling allows for as many as 28 wells on a single well pad, producers recover more oil using fewer wells and less than .5 percent of the surface area in North Dakota. As of April 2015, North Dakota had just 12,537 wells that produced more than 1.17 million barrels per day compared to California’s onshore production, which was just 522,500 barrels from 49,149 wells.
The North Dakota Department of Mineral Resources estimates that once the Bakken is fully developed, every square mile beneath the surface may be developed by as many as 60,000 wells. Because of horizontal drilling and multi-well pads, however, the impact will not be on the surface, but rather remain underground. As technology advances, industry will be able to become even more efficient and recover more oil from existing well pads further reducing the footprint of oil and gas development.