I changed the brake pads on my 2012 Honda CR-V, how do I responsibly dispose of the original brake pads?
The pads are just regular metal waste. Dispose of them in the same way you would dispose of anything that is made from metal. If there's a metal waste container nearby, you can put them there. The metal can then be reused. If not, well, I wouldn't worry too much about their disposal as they don't contain that much metal and thus the additional value to the society by disposing of them properly is not that high. Mixing them with other garbage is not going to be a major problem. After all, they are not hazardous waste (brake pads don't contain asbestos anymore). Also, if you drive around too much trying to find where to put the old brake pads, the exhaust emissions of your car will be a far worse problem than improper disposal.
Brake rotors would be an entirely different thing. They contain far more metal than brake pads, and thus, driving around to find a metal waste container might be worth it for the society, if you feel like doing the good thing. Obviously, it will be you who pays for the gasoline used by your car.