Business First of Louisville, March 13, 2009 A lengthy union battle to organize nurses at Louisville’s Norton Audubon Hospital on Poplar Level Road has come to a halt. On Thursday, the National Labor Relations Board approved a request on behalf of the Nurses Professional Organization to withdraw a petition for an election, according to a press release from Norton Healthcare Inc. “This concludes a process that began with the original nurses union election at Norton Audubon in March 1994,” the statement said. ... Nurses