WASHINGTON, D.C. -- President Obama yesterday signed the Car Allowance Rebate System (C.A.R.S.) bill, also known as “Cash for Clunkers,” into law.

The National Highway Traffic Safety Administration will oversee the program, and has about 30 days to develop guidelines for implementation of the program. A Web site CARS.gov has already gone live and offers some basic details about the program, which is expected to take effect by Aug. 1.

The law provides $1 billion in funding for the program, which will be available until November. CARS has been projected to provide 250,000 motorists with the opportunity to trade in their present cars for vouchers worth up to $4,500 to assist in purchasing for a more fuel-efficient and environmentally-friendly alternative. One caveat to the offer: Motorists will not be eligible for the trade-in value of the vehicle on top of the C.A.R.S. funding.