Adamsburg crews responded late Wednesday to reports of "an unknown substance" discovered in six containers inside a storm drain in a concrete culvert under a bridge at 120 Hamilton St. near Penn Borough.  The substance, described as a clear liquid found in gallon milk jugs and antifreeze containers, was determined to be nonhazardous after the entry team in Level B ensembles tested for PH and used 5 gas meters to make the final assessment.