married spouses, further extending rights to LGBTQ+ Washingtonians. Opponents gathered signatures to put 2009 Washington Referendum 71 on the ballot in an attempt to repeal the bill. Washington voters approved the measure 53% to 47% in the country's first statewide referendum to extend domestic partnership rights to LGBT citizens. On January 4, 2012, Gregoire announced her support for same-sex marriage and pledged to sign a marriage bill if it were passed by the legislature. The bill was passed on February 8, 2012. Gregoire signed the bill on February 13. Opponents of the bill collected the necessary signatures to place it Referendum 74 on the November ballot, where it was approved by 53.7% of the voters. The law took effect December 6. Transportation In March 2006, Gregoire's requested bill, SB 6508, was signed into law. The law directly affected transportation fuels by requiring fuel suppliers to ensure that 2% of the diesel and 2% of the gasoline they provide for sale is biodiesel and ethanol as of December 2008. The measure was the nation's first requirement for alternative fuels. In 2009, Gregoire led public and political support to build two of the nation's largest infrastructure projects, replacement of the 520 floating bridge and a plan to replace the aging and earthquake vulnerable State Route 99 Alaskan Way Viaduct with a deep bore tunnel. At the time, the tunnel was the world's largest deep bore tunnel project. The 520 floating bridge is the world's longest floating bridge and opened in 2016. Seattle's new waterfront tunnel opened in 2019, making way for a revitalized new waterfront. Bridging transportation and the environment in 2010, Gregoire announced the nation's first “electric highway,” an initial network of electric vehicle recharging stations along the I-5 corridor. Additionally, she used more than $13 million in Recovery Act grants to help train Washington workers for “green-collar” jobs in energy efficiency and renewable energy industries. Along with Oregon Governor Kitzhaber, Gregoire announced support for the Columbia River Crossing to replace the aging I-5 bridge connecting Washington and Oregon. Gregoire signed the 2011–2013 transportation budget putting 30,000 people to work and investing $5.6 billion into more than 800 transportation construction projects. Medical marijuana Together with Governor Lincoln Chaffee (I-RI), on November 30, 2011, Gregoire filed a petition with the Drug Enforcement Administration (DEA) asking to reschedule marijuana as a Schedule 2 drug, allowing its use for treatment as prescribed by doctors