Asphalt book coverAsphalt: A History
By Kenneth O’Reilly
344 pp. University of Nebraska Press, Jul. 2021.
Hardcover, $29.95; ePub or PDF, $29.95; Amazon Kindle, $22.70.

In this, his latest book, historian Kenneth O’Reilly tells the story of what he persuasively argues is one of humankind’s most underappreciated resources. Asphalt, also known as bitumen, is an abundant, versatile, highly concentrated form of petroleum that has been with our species since time immemorial, and has gradually, in O’Reilly’s view, come to be taken for granted. Few people fully grasp the degree to which it permeates modern life, contends O’Reilly; and fewer still are aware of what a fascinating study in contradictions it is, symbolizing both prosperity and damnation, liberty and subjugation, death and life extension, environmental ruin and restoration. These and many other dualities of asphalt are thoroughly and engagingly explored in Asphalt: A History.

O’Reilly divides his history into two parts. Part one begins with the initial formation of petroleum and its constituent parts, including asphalt, millions of years ago from the buried remains of dead organisms, and ends just before the dawn of the age of blacktop pavement in America. Part two recounts how the widespread use of asphalt not only in paving, but also in roofing, adhesives, coatings and countless other applications, has utterly transformed our lives over the past century and a half. This second part also has some interesting thoughts on asphalt’s potential role in the transition to a green energy future.

The first theme to emerge from this sweeping history is the link between asphalt and death. O’Reilly traces this link all the way back to the innumerable deaths of algae, phytoplankton and other marine organisms that had to occur for asphalt to exist in the first place. He then describes how some of that same asphalt caused additional death by rising to the Earth’s surface and forming tar pits that fatally trapped untold numbers of unsuspecting animals, including at least one human. He then proceeds to chronicle how prehistoric humans used asphalt from these same pits in the creation of deadly weapons. And, citing references to asphalt in the Bible and other classical texts, he shows how the bubbling black goo came to be closely associated with a dreaded abode of the dead—hell.

This connection between asphalt and death has persisted over the millennia. It was the ancient Egyptians’ use of asphalt to desiccate dead bodies during the mummification process that drove a thriving trade in asphalt harvested from the Dead Sea. Dead Sea asphalt went on to cause death in the form of a war waged over its commercial control during the fourth century B.C., which O’Reilly refers to as “the Middle East’s first fossil-fuel war.” O’Reilly also implicates asphalt in the Roman civil wars, the untimely demise of Cleopatra and the destruction of Nagasaki, Japan by an atomic bomb with asphalt-coated casing seams. He shows how asphalt and its production pervaded the lives of Holocaust prisoners, so much so that it comes up often in survivors’ accounts. And he laments the vast numbers of both human and animal fatalities that occur on roads and highways made from asphalt.

Asphalt causes additional death when it leaks into the environment, as it has done entirely too often. Among the worst offenders on this score are the many World War II-era “asphalt disposal areas” containing leftover material from battlefield construction projects and residuals from the production of oil used by the U.S. military. O’Reilly also pulls back the veil on the horrifying ecological toll exacted by Canadian tar sands production, a toll that includes one of the worst inland oil spills in American history and the massive release of cancer-causing effluents into the Athabasca River from tailings ponds large enough to be seen from space.

Yet for all the death that can be laid at asphalt’s feet, O’Reilly catalogs a host of ways in which asphalt also prevents death. In the late 1800s, the move from dirt roads to asphalt-paved streets helped substantially increase life expectancy by tamping down disease spread. During World War II, the advantages of asphalt runways over concrete runways were instrumental in the Allies’ victory over Hitler. During the Second Gulf War, asphalt pavement served as a means of combating improvised explosive devices (IEDs). Asphalt also preserves life by halting the spread of toxic waste: Its impermeability makes it a crucial ingredient in sealants used to contain low- and intermediate-level radioactive waste and reduce leakage at EPA-designated Superfund sites.

Just as asphalt on land brings both harm and benefit, so asphalt in the ocean can be both a pollutant and an integral part of nature. When it enters the ocean from a stricken tanker or a blown-out deepwater well, it’s of course a pollutant that causes grave injury to marine life. But when it enters through a natural seep on the seafloor known as an asphalt volcano, it’s a bustling haven for life. Asphalt volcanoes were completely unknown to science until 2003. Their main feature is an elegant flower-like structure called a tar lily, which forms when a stream of molten asphalt solidifies in cold water. Tar lilies can be up to 60 feet tall and a third of a mile across, and they provide habitat for sea cucumbers, sponges, octopi and many other bottom-dwelling creatures. O’Reilly’s descriptions of these unlikely marine population centers—which have been likened to hydrocarbon versions of coral reefs—are evocative and fascinating.

Another of asphalt’s dualities is that of climate foe and climate friend. The respective villain and hero of this story are natural asphalt mined from places like the Canadian tar sands and asphalt produced as a byproduct of oil refining, with the former contributing to climate change and the latter ameliorating it. Natural asphalt is processed into gasoline and diesel fuel that are then burned in automobile engines, thus adding to climate change. Refined asphalt, on the other hand, is used to make things like blacktop pavement and roof shingles, which lock up climate change-causing gasses rather than freeing them into the atmosphere.

The author touches on a number of efforts to make asphalt even more environmentally friendly. One of these is the development of permeable pavement, which is designed to prevent flooding and pollution from urban runoff. O’Reilly seems agnostic on the potential of permeable pavement, observing that it presents significant technical challenges—including inferior load-bearing capacity and a tendency to make storm drains clog—that must be overcome before it can be widely adopted. He’s similarly unsure about bioasphalt, correctly noting that it has yet to be proven on a large scale. Solar road surfaces are the technology that most excites O’Reilly, but sadly it’s a misbegotten excitement. While the author touts the use of solar photovoltaic surfacing on France’s Wattway Road, he neglects to mention that this first-of-its-kind project proved to be an expensive flop.

Asphalt’s remaining dualities provide rich fodder for O’Reilly’s analysis. He argues cogently that racial inequities have been hugely amplified by the spatial boundaries created by asphalt pavement. He reveals how asphalt both aids and hinders America’s enemies—describing, for instance, how highways provide both a prime funding source for the Taliban and a source of gainful employment that deters young men from joining the insurgency’s ranks. There’s also the duality of the hidden versus the public, with asphalt serving both as a cloak for smuggled contraband and a proud central feature of some of the modern world’s crowning feats of engineering.

Perhaps the most important virtue of asphalt is that it’s completely recyclable—indeed, as we learn from O’Reilly, blacktop pavement is the most recycled material in the world. Moreover, a variety of other materials in need of recycling, such as discarded tires and roof shingles, can easily be incorporated into blacktop mixes. O’Reilly says he looks forward to a day when humanity is no longer producing any new asphalt and is instead continually recycling what has already been produced. While the question of how we might attain this grand ideal is beyond the scope of Asphalt, the book is nonetheless a stellar survey of the path that brought us to where we are today with asphalt.

 

Teaser photo credit: By Silverije – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=37085244