No injuries were reported after a tractor-trailer accident at 8:15 a.m. Friday on Interstate 80 in Union Township. Robert D. Park, 57, of Butler was traveling westbound in the right-hand lane when he apparently fell asleep. His tractor-trailer traveled off the north berm and then in a westerly direction parallel with the roadway. At that point, it partially scaled the adjacent embankment and traveled along the same for 128 feet before transcending from the embankment. His tractor-trailer proceeded to travel 440 feet until overturning to its right one-half revolution. It came to a rest on its roof at which point part of its liquid cargo of transmix leaked from the trailing unit. State police were assisted by the Sandy Township Fire Department, DuSan EMS, PennDOT, Eagle Hazmat & Spill Response Services, DEP and Bricen Towing.