Janesville firefighters are back at the city’s landfill.  Firefighters were first called to the landfill about 11:00 p.m. Tuesday night and spent more than four-hours dousing burning debris.  They were called back again Wednesday morning and spent most of the day putting-out hot spots.  A flair-up again about 11:00  p.m. Wednesday forced their return, and they expect to stay most of the Thursday ensuring the fire is extinguished.