The Texas Senate passed a bill May 5 to help bring the state into federal clean air compliance, the Dallas Morning News reported.

The proposal by Sen. Chris Harris, R-Arlington, combined with current funding, would raise about $640 million over the next four years for the Texas Emissions Reduction Program, which would target diesel emissions.

Lawmakers say the proposal awards grants to speed up business’ voluntary retirement of older, higher-polluting diesel equipment, and it also pays for research into clean-air technologies.

The U.S. Environmental Protection Agency has required the Lone Star State to reduce its emissions by 16.3 tons a day in the Dallas-Fort Worth area and 18.9 tons a day in the Houston area by 2007, the newspaper reported.

If those areas fail to meet the emissions standards, the state could lose millions of dollars in federal highway funds.

The bill would raise the current $13 vehicle title transfer fee to $33 in areas of the state that don’t meet clean-air standards or those that barely avoid the cut. The fee would increase to $25 for the rest of the state.

HB1365 would also increase the surcharge on the sale or lease of off-road diesel equipment from 1 percent to 2 percent.

It would lower the surcharge on the sale or lease of on-road diesel equipment from 2.5 percent to 2 percent, but the surcharge would be expanded to newer vehicles.

The House of Representatives has already approved the measure, but its funding sources were different from the Senate. In the House version, the money would have been raised through a 3-cent-a-gallon tax hike on diesel fuel.

If the House fails to concur with the Senate changes to the bill, a committee of House and Senate members will be assigned to work out the differences.