By early 2010, when Melgen formally joined GFS, Menendez had already taken on a key role in backing the natural gas bill, joining Democratic Senate Majority Leader Harry Reid of Nevada and Republican Sen. Orrin Hatch of Utah as out-front sponsors.The NAT GAS Act quickly drew energy and environmental battle lines. Oil and alternative energy magnate T. Boone Pickens led corporate natural gas industry backers of the bill, aided by the Obama administration and influential environmental groups. Arrayed against the bill were top oil and coal firms and even some green activists, joined by industrialists David and Charles Koch, whose political action group, Americans for Prosperity, harnessed opposition from conservative groups. Green said he did not authorize or hire any lobbyists on behalf of GFS because he was skeptical about broadening into the markets for on-road trucks. But he did not block the activities of Muller, who in addition to his consulting role with GFS, had also started his own firm, Diesel 2 Gas. It aimed to license GFS technology and use the firm's parts to outfit on-road trucks. In June 2010, representing both GFS and Diesel 2 Gas, Muller testified before an EPA panel in Ann Arbor, Mich., about what he called "cumbersome and unnecessary" rules that hurt GFS and other natural gas firms. The EPA agreed to alter its regulations in April 2011. Between 2009 and 2011, Muller also ran an independent consulting firm, Muller Group Inc., which paid $220,000 to lobbyists from Brownstein Hyatt Farber Schreck LLP to lobby for the NAT GAS Act and related issues. Muller said he accompanied the lobbyists in at least one meeting with Menendez' staff about the bill but could not recall details. Melgen and Muller joined Menendez at a signing ceremony in Miami in January 2010 for the senator's book, "Growing American Roots." And last June, they joined Menendez at the annual U.S.-Spain Council Annual Forum in Jersey City.