Reincarnating Trash on the Big Island

By Christina Larson

Although not a fact advertised prominently in Hawaiian tourist brochures, the island of Oahu has a trash problem. The scenic island, renowned for its lush and varied ecosystems and such popular destinations as Waikiki Beach and Pearl Harbor, is home to approximately one million Honolulu residents and some five million visitors each year. Yet it has only one large landfill and one waste management plant. Both are now at capacity. Local officials are exploring the possibility of exporting Hawaii’s trash, bound in plastic and loaded on barges, at great expense, to Washington state.

Perhaps, though, rubbish problem is not quite right. To Marian Chertow, Ph.D. ’00, associate professor of industrial environmental management at F&ES, one man’s trash is another man’s raw material. She is fond of asking, “Why waste waste?” While most visitors to Oahu first trek to the beach or hike up a volcano on research expeditions, Chertow typically bypasses such picturesque locales and heads straight for a nondescript industrial park, where she believes something “magical” is happening.

Industrial ecology, an emerging field of study, may sound like an oxymoron, but it views urban landscapes much like scientists view natural ecosystems. “It is a funny use of two words,” Chertow explains. “We usually think of industry as opposed to ecology.” But she’s quick to explain the poetry of the phrase. In her work she traces the flow of materials, water and energy through a manmade system, much the way a biologist or zoologist traces the life cycle of plants and animals through an ecosystem. In a natural system, there is a continuum of interactions based on the principles of reuse and equilibrium. Think of a chain of predators, in which a zebra munches on shrubs before being devoured by a lion. In her research, Chertow focuses on the urban jungle. She traces the pathways of steam and sludge through smokestacks and drainage pipes to ask whether output by one industrial process may, in fact, be valuable input for another.

The answer, quite often, is yes. One place to look is Oahu’s largest manufacturing complex. For reasons of economy and convenience, several facilities in Campbell Industrial Park have already begun to share and reuse waste. For instance, the main power plant started scouting for alternatives to expensive imported coal, which must be brought to Hawaii by boat. Its managers got creative. Instead of looking only at materials traditionally labeled and sold as fuel, they began to examine the range of petroleum-based products being thrown away on the island. This included used tires discarded by car rental companies, used motor oil collected at gas stations and “used activated carbon,” a compound employed by the municipal water board as part of its purification process. These companies, for their part, had the burden of paying high costs to dispose of their waste materials on the island. And so a series of deals was brokered, whereby the power plant buys these nontraditional fuel materials at a lower price than it would pay to import an equivalent amount of coal (it still uses some coal for its operation), and the companies save on landfill charges. Scientists call this form of mutually beneficial relationship, “industrial symbiosis.”

Practical considerations are what motivated these companies to form partnerships, but from a broader perspective, what fascinates scientists like Chertow is the vast spectrum of implications of such unconventional resource sharing and reuse. “Think about the benefits upstream and the conservation of materials,” she says, noting that thanks to such trash swapping, the Oahu power plant has already burned some 18,000 fewer tons of coal. The fact that these factories are reusing materials means that fewer minerals and metals need to be hoisted out of the ground; fewer ecosystems will be disrupted in the messy process of extraction; and there may be fewer future geopolitical skirmishes over access to resources and, perhaps one day, sea lanes. “It’s ultimately,” says Chertow, “about sustainability.”

Extend this frame of analysis beyond a single industrial complex to a city, an island, a region or even the planet. “The broader conceptual framework,” says Journal of Industrial Ecology editor Reid Lifset, “is to ask questions about waste and waste generation—why we have the stuff we throw out and then why we throw it out.” At a time of heightened global concern about resource scarcity, which is driven by rising demand and uncertainty about the impacts of climate change, the need for a better system of tracking materials use has never been more apparent.

Chertow, whose research has also taken her to Puerto Rico, China and India, emphasizes the need to think about garbage in a granular way—not just as junk, but as material flows comprising parts—and then ask who has the need for those parts. Likely someone wants exactly what someone else is selling. It’s the difference between letting boxes in an attic gather dust and separating out the piles of vintage clothes from the paperbacks, the porcelain dolls from the costume jewelry, in order to sell them on eBay.