Cynthia Walter, from the Sierra Club, and other participants rallied and signed petitions in Schenley Park during a rally against Shale gas drilling in Pittsburgh, Saturday, Sept. 22, 2012. (AP ... more 
Cynthia Walter, from the Sierra Club, and other participants rallied and signed petitions in Schenley Park during a rally against Shale gas drilling in Pittsburgh, Saturday, Sept. 22, 2012. (AP Photo/John Heller) less 
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Associated Press | Photo By John Heller
Sat, Sep 22, 2012 7:47 PM EDT