The Air Transport Association will "work positively with Congress to help shape" a bill governing carbon emissions, says the group's environmental affairs vice president. The Clean Energy and Security Act of 2009 would affect aviation in several ways: First, airlines' jet fuel purchases would receive an additional tax as a result of emissions allowances that would be tacked on to the cost of fuel, under cap-and-trade measures outlined in the bill. ATA is concerned that this carbon tax could be compounded by another proposal for the EPA to set new aircraft and engine emissions standards, thus raising the price of aircraft and engines. Finally, the bill calls for "a low carbon fuel standard for all transportation fuels," including jet fuel. But by leaving out details regarding where producers should invest, the draft bill leaves open the possibility that suppliers may focus on meeting carbon mandates through alternatives to gasoline, rather than seeking out alternatives to jet fuel.