NEW YORK – New York City is going to impose strict environmental standards on cars and vans it buys, and require that diesel trucks and buses be modified in a effort to reduce harmful emissions, according to the New York Times. The city council is scheduled to vote to approve a package of environmental bills intended to reduce the tailpipe emissions that contribute to cancer, heart disease, and respiratory problems. Additional costs from using clean fuel and modifying engines are expected to be offset by the savings in fuel consumption and lower health care costs. Under the bills, the city would be forced to buy only cars and vans that are the least polluting models available whenever it replaces vehicles currently in use. The bills would also require the city's fleet to be efficient enough to reduce its overall fuel costs by 20 percent in a decade. Councilman James F. Gennaro said that the legislation had already been reviewed by Mayor Bloomberg's administration and that he expects it to pass easily. The bills also include a pilot program involving a handful of street sweepers powered by compressed natural gas.