By Donella Meadows
–March 30, 1989–
Exxon has just hired 100 people at $16 an hour to “clean up” the massive oil spill near Valdez.
The government estimates that “cleaning up” the radioactive contamination at its weapons plants will cost over $100 billion.
The states have submitted a list of 2000 hazardous waste sites for priority “clean-up” under Superfund.
What does “clean up” mean? When the technicians scour the oil-coated shore or go behind skull-bedecked warning fences, put on moon-suits, and rev up their vacuum-cleaner trucks, what, exactly, is going on? What is left when they’re done? Where do they empty the vacuum-cleaner bags?
I’ve been asking those questions for months. The answers I get depend on what site I’m asking about and what kind of hazardous substance. About the only firm conclusion I’ve come to is that “clean up” is rarely the right expression for what we do with toxic messes. “Wall off” might be more accurate, or “immobilize for awhile”, or “put somewhere else”, or “hide”.
For example, the number one site on the Superfund list, the Lipari Landfill in New Jersey is an eight-acre dump containing three million gallons of mixed chemicals. Fumes from the dump brought tears to the eyes of neighbors; a lake downstream occasionally turned purple or orange. The “clean-up” plan called for “containment”. The site was surrounded by an underground concrete wall and covered with a cap of clay and plastic. Chemicals continue to leach out in the groundwater, and fumes still come through the cap.
Now the site will be “re-cleaned”. The lake will be dredged, the bottom mud put somewhere else, and the landfill will be flushed with water for seven years. The leachate from the flushing will be collected, treated, and put somewhere else.
Capping, containment, and putting somewhere else are the cheapest options, and the most common, as indicated by these Superfund case study summaries by the Office of Technology Assessment:
Chemical Control Corporation, Elizabeth NJ: “Unproven solidification technology was selected to treat … highly contaminated subsurface soil…. The cleanup will leave untreated contamination on the site.”
Compass Industries, Tulsa County OK: “Capping was called a cost-effective, permanent cleanup even though it does not provide permanent protection…. Treatment of contaminated groundwater is not yet planned.”
Conservation Chemical Company, Kansas City, MO: “Pumping contaminated groundwater and capping the site were chosen instead of … excavation and treatment of contaminated soil. Water treatment cannot remove all the diverse contaminants at the site.”
A report by the Hazardous Waste Treatment Council estimates that only about 8% of the remedies selected for Superfund cleanup use the maximum technical option required by law. And maximum treatment at its best is still not “cleaning up”.
In one of the best Superfund operations, PCB-contaminated electric equipment abandoned in a warehouse in North Carolina was hauled to a special toxics facility in Alabama. The material was shredded, packaged, and sent to an incinerator in Chicago. In the flames the PCBs became water vapor, carbon dioxide (a greenhouse gas), and various chlorine compounds (causes of smog and stratospheric ozone depletion). The ash went back to Alabama to be landfilled. Much cleaner, but not clean. And very expensive.
For some hazardous materials “clean” is a possibility; for others it’s not. Here’s the best we can hope for:
- Strong acids and bases can be neutralized.
- Cyanides can be made harmless by chemical reaction.
- Organic chemicals, including petroleum and pesticides, can be digested by natural organisms in a few cases. Some fall apart when exposed to sunlight. All can be broken down into water, carbon dioxide, sulfur dioxide, and chlorine compounds, if carefully incinerated at the right temperatures.
- Radioactive elements cannot be “cleaned up”. They must be strictly sequestered from wind, water, and all life forms until they break down naturally according to their internal atomic clocks. Their half-lives (the time it takes them to decay to one-half their original quantity) vary — 12.5 years for tritium, 33 years for cesium-137, 24,000 years for plutonium-239, 4.5 billion years for uranium-238.
- Heavy metals like lead, cadmium, and mercury last forever.
Even those “clean up” efforts that are chemically possible are foiled if the toxic materials become dispersed in soil, carried off in water, absorbed into living things, or wafted away in the air, or if they are mixed up together. Scooping the spilled oil out of the water and off the rocks of Prince William Sound is simply impossible.
I suggest that we stop using the words “clean up” when referring to hazardous materials and start facing the fact that we are risking irreversible damage and making uncleanable messes. Then, maybe, we’ll start handling dangerous chemicals with the seriousness they require.
Next week: A nation that doesn’t have to clean up — Denmark’s model hazardous waste disposal system.
Copyright Sustainability Institute 1989