BART is planning to extend its line from Fremont to San Jose, and they plan on recycling in the process. To handle the problem of noise along the line, they will be shredding 250,000 tires, wrapping them in fabric, and laying eighteen inches of them right beneath the tracks. This, BART says, will help reduce vibrations.

The proposed system is not only ecologically sound, removing one-quarter million tires from landfills and putting them to good use. At $150 per foot, it is also $100 cheaper than other, more conventional methods used to cushion tracks.
Read More at ABC 7.