By now, landfills are infamous to just about everyone. We know they stink, we know they harbor a lot of nasty waste and while we don’t necessarily understand all of the science behind creating and maintaining these things, something in our gut tells us that landfills are not good for us or the environment.
The big problem with landfills is that they cause the formation of toxic leachate. Leachate is liquid run-off created when rain-water and/or storm-water percolates through the debris buried in landfills. Remember from other articles I have labeled water as the most dangerous liquid known to man. Water, the universal solvent, will dissolve virtually everything it comes into contact with. Since landfills are full of toxic materials, it only stands to reason that the water percolating through these masses is going to contain a lot of toxic material as well.
Weird things happen in a landfill. Bacteria help to decompose garbage and other wastes a high concentration of stinky, nasty, black ammonia water is produced. Furthermore, the bacteria action in landfills causes the temperature to rise and the pH to drop. Many metals (Chromium, Zinc for example) that are insoluble at a neutral pH, are dissolved and released into the environment quickly in the low pH created by active bacteria.
The danger to our water supplies is quite clear. Leachate must not be allowed to escape into the environment.
The current solutions for treating landfill leachate are inadequate and costly. They include bio-reactors ( a large tank using bacteria to further break down the leachate), air stripping, chemical precipitation, and a few other approaches. Unfortunately, depending on the leachate, a particular technology may or may not work. Only the installation of the actual treatment technology can determine that for sure.
To illustrate what a headache this is, realize that a typical landfill will produce 30 – 60,000 gallons of toxic leachate per day. The cost of a bio-reactor for such a plan ranges in the 2.5 – 3 million dollar range. Can you imagine spending $3 million and not knowing if the machine will work or not.