"Cash for Clunkers" environmental cost/benefit balance seems to have been negative.

"According to the Automotive Recyclers Association (ARA), almost 100% of a vehicle can be recycled."

Even the fluids can be reused.... Transmission and brake fluids, anti-freeze, oil, gasoline, diesel and Freon from air conditioners are harvested at scrap yards for use in other vehicles. However, still-functioning engines are the most valuable part of a scrapped car....

Many of the cars that were traded in during Cash for Clunkers were perfectly functioning cars in good condition, and excellent candidates to have their engines and other parts recycled. With the engine destroyed, many clunkers bypassed the recycling companies and went straight to junkyards to be crushed and shredded.... [The engines were] destroyed to prevent the vehicles from being resold and taking the road again.....

[Cash for Clunkers] mandated that the clunkers be crushed or shredded within 180 days, regardless of whether all the usable parts were salvaged or not... Cars that are shredded are turned into small, palm-sized pieces of metal... For each ton of metal recovered by a shredding facility, roughly 500 pounds of shredder residue are produced, meaning about 3 to 4.5 million tons of shredder residue is sent to landfills every year....

Well, that's the perspective of the recycling industry, and it's all information that was known when the program was adopted. This isn't news, just an industry press release. That should make us skeptical, but also, if it's true, more critical of the government, since (I assume) they knew all this and did it anyway.