On UPWARD slope in 4WD on icy intersection ,proceeding less than 5 mph, emergency braking as a car dead stopped at intersection on green light, hit brakes hard and brake pedal and gas pedal both engaged,, van kept moving forward,, pumped once same effect, ran in to rear of stopped car at 2-3 mph.. I was wearing work boots and gas pedal and brake pedal both at same elevation. brake pedal to close to the gas pedal.. Vehicle is a 4 wd 2500 series van. I have used van for 5,000 miles so I am used to the vehicles characteristics. Practiced a recreation a few times with same result, brake and gas pedal both get depressed upon panic hit with foot.