From the Sky and to the Depths: PA Supreme Court Considers Subsurface Trespass
A maxim of real property rights is “to whomever the soil belongs, he owns also to the sky and to the depths,” which is derived from the Latin expression cujus est solum, ejus est usque ad coelum et ad infersos. This maxim, referred to as the ad coelum doctrine, proposes that a landowner owns everything above and below the property to an indefinite extent.
Since the nineteenth century, Pennsylvania courts have applied the “rule of capture.” This is a principle of oil and gas law stating that there is no liability for the drainage of oil and gas under the lands of another so long as there has been no physical trespass on the surface. The principle is derived from a physical property of fluids, in which fluids naturally move across a pressure gradient from high to low. This flow does not respect property boundaries. If a property owner drills a well on their property but the well does not physically pass onto her neighbor’s property, she is not a trespasser if oil and gas are drained from her neighbor’s property into her well through a common reservoir that extends through both of their properties.
In an attempt to address the application of ancient legal precepts to the modern world, the Pennsylvania Supreme Court recently issued its much-anticipated ruling in Briggs v. Southwestern Energy Production Company. Briggs addressed a topic of great interest to the oil and gas industry: whether the rule of capture is applicable when the means of production is a technique known as hydraulic fracturing. Hydraulic fracturing, commonly referred to as “fracking,” involves pumping large quantities of fluids at a high pressure down a wellbore, creating fractures in the target rock formation. Hydraulic fracturing fluid commonly consists of water, proppant, and chemical additives that open and enlarge fractures within the rock formation. These fractures can extend several hundred feet away from the wellbore. The proppants—sand, ceramic pellets, and other incompressible particles—hold open the newly created fractures. The fluid is withdrawn from the well, leaving the proppants in place to hold the fissures open. The technique enhances the drainage of oil or gas into the wellbore, where it can be captured.
While fracking is not a new production technique, it has gained recognition as a cost effective means to produce oil and gas from unconventional reservoirs. Unconventional reservoirs are so named because the oil and gas are often highly dispersed within the surrounding rock formations, rather than occurring in concentrated underground locations, as are found in conventional reservoirs. The development of these unconventional reservoirs has led to the United States assuming its role as a leader in global oil and gas production.
In Briggs, the Pennsylvania Supreme Court addressed application of the rule of capture to the use of fracking. This issue rested on the determination of whether a physical intrusion on the neighboring landowner’s property takes place any time oil or natural gas migrates across property lines as a result of fracking. The argument opposing application of the rule of capture was that fracking should be viewed differently because it involves an artificially-created means of drainage. The Court rejected this view, holding that the key to determining whether the rule of capture applies is not the production technique used to extract the oil and gas. Instead, the key issue is whether, irrespective of the means of production, there has been a physical intrusion on the neighbor’s property.
By focusing on whether hydraulic fracturing resulted in an intrusion to the neighbor’s subsurface, the Court’s ruling appears to reaffirm the traditional notion that whoever owns the land owns everything below it. The extent to which a property owner can preclude intrusion into the subsurface has a wider application than the energy industry. The Pennsylvania Supreme Court noted Southwestern Energy’s position that uncertainty over this issue could imperil carbon sequestration projects, energy storage wells, and waste disposal sites. The Pennsylvania Supreme Court, however, declined to squarely address this issue on the basis that it had not been properly framed for the Court’s consideration.
The ad coelum doctrine is not an absolute principle, having given way to technological developments where air rights are concerned. It is well established that property ownership does not extend upward, indefinitely. Air traffic can pass over a property without trespass, but a neighboring property owner may not be permitted to build a sign that overhangs a property boundary. The extent of a property owner’s interests in the space of the air above the surface is measured by the extent that he can make use of his property.
Left unanswered by Briggs is whether there is a downward limit to the ad coelum doctrine. The extent to which absolute subsurface rights remain in place will no doubt continue to be challenged as more subsurface areas are developed.
