Analysis of recent disasters shows vast majority of debris unrecycled
When a disaster such as a hurricane, fire, flood or tornado strikes, a community may be confronted with well over a year’s worth of debris to manage in a matter of hours. At the time the Northridge earthquake hit Los Angeles in 1994, for example, the Environmental Protection Agency (EPA) said a single local company processed 150 tons of construction and demolition (C&D) materials daily. After the earthquake, the city picked up as much as 10,000 tons of C&D materials per day. Ultimately, the disaster generated 7 million cu. yds. of debris.
Other disasters keep pace. The EPA said Hurricane Iniki in September 1992 created 5 million cu. yds. of debris in Kauai, Hawaii. Mecklenburg County, North Carolina, faced 2 million cu. yds. of green materials after Hurricane Hugo in September 1989. In 1991 in Florida, Hurricane Andrew generated 43 million cu. yds. of disaster debris just in Metro-Dade County. Hurricane Katrina in 2005 reportedly churned out 50 million tons wood debris alone.
Recycling debris offers potential benefits, from saving money and space compared to landfill disposal to generating energy and reducing pollution compared to open burning, which are the usual methods. The EPA noted that green materials such as trees and shrubs can be recycled into compost or mulch, concrete and asphalt can be crushed and used for road building, metal can be recycled by scrap metal dealers, brick can be sold intact for reuse or ground for landscaping applications and dirt left as sediment can be used in agriculture or as landfill cover.
The scale of the debris generated by major disasters makes this a major opportunity as well as a major problem. For instance, one estimate said the 50 million tons of Katrina debris could have provided enough wood to make a 10 percent mix with the fuel for every U.S. coal-fired power plant for a full year.
Unfortunately, the vast majority of the Katrina debris, as well as debris from other disasters, is not recycled despite decades of recyclers urging emergency management authorities to encourage and prepare for recycling instead of landfilling or burning wreckage left behind by storms, earthquakes, fires and other disasters.
“It’s an important topic and one we haven’t addressed very effectively,” said Kristiina Vogt, professor of Ecosystem Management at the University of Washington. “Most of the time, it just sits there.”
Numerous problems confound efforts to recycle disaster debris. The recyclables are usually heavily commingled, with trees and construction debris mixed in with appliances and sediment, including a sizable component of hazardous materials. Disasters are hard to predict, making it hard to plan in advance by, for instance, siting large recycling facilities where they’re needed.
Post-disaster relief is often focused on simply clearing roads and rescuing inhabitants. “When disaster strikes,” Vogt noted, “you just deal with the people.” There is also a lack of good technology, such as self-contained portable systems for such jobs as gasifying woody debris or removing the paper from wallboard so it can be recycled as gypsum.
Some of this is starting to change. The EPA and Federal Emergency Management Association (FEMA) both provide direction about how to recycle debris to communities preparing for possible disasters. For instance, FEMA advises planners to create lists of recyclable materials as part of their post-disaster debris management plans. The agency emphasizes focusing on end-user markets that can employ recycled disaster debris, including identifying recyclable product buyers and even securing sales of recyclable materials prior to a disaster striking.
Vogt is working with the University of North Dakota on a portable system for turning woody and vegetative debris into methanol and diesel fuel. The liquid fuels are easier to burn for energy generation and other uses, and are more energy-dense than wood or similar materials, so they are more economical to ship by truck. Other developers are working on similarly portable gasification systems to transform organic debris into fuel for generating electricity.
None of these technologies is in full production yet, however. Vogt said that funding is the problem, and that it’s hard to get investors to support a product that will only be used in the event of a sizable disaster. Still, however, on a national scale, disasters happen regularly. The March 2012 tornadoes in Indiana and Kentucky and the forest fires in Texas in 2011, while not on the scale of a hurricane or earthquake, all created sizable amounts of debris, especially compared to the normal quantities of materials generated in the smaller communities where these disasters struck.
Large or small, few communities can manage an effective recycling response when hit with a large disaster. What Vogt would like to see is some sort of federal initiative to help communities recycle what is left over after fire, flood, storm or earthquake. “We need to have a better national program,” she said. “Instead of just putting money into giving people trailers to live in, we should try to use that debris.”
Some experiences indicate that disaster debris can effectively be recycled. The city of Los Angeles, for example, worked to recycle the Northridge earthquake debris because of its overriding recycling goals. After two months of negotiating with the city, FEMA, which was overseeing post-disaster debris management, allowed the city to recycle debris. Contractors began separate collections of wood, metal, dirt, concrete and asphalt and other recyclables.
Concrete and asphalt were crushed, mixed with dirt and sold for road-building sub-base. Dirt was used as landfill cover and soil amendment. Fine pieces of wood sold by the cubic yard for landscaping, while coarse pieces were used for cogeneration fuel or compost. Ground up brick went to baseball infields or landscaping. Scrap metal dealers recycled metal materials.
The city’s pilot test suggested a potential 82 percent recycling rate. Eventually almost 56 percent of all materials collected since the earthquake were recycled for less than disposal would have cost. With more recycling capacity, the city estimated, a recycling rate of over 86 percent was achievable.
While the Northridge earthquake happened 18 years ago, similar successes in recycling disaster debris since have been scarce. But with greater interest in recycling, it may be time for disasters to begin to contribute more to the field. “The climate’s starting to change,” Vogt said, “but it’s been very difficult to get people even thinking of this.”