Milwaukee County residents are on high alert after human remains were discovered in three separate instances since last week, RadarOnline.com has learned. Local police said they are investigating unidentified human remains found in the area of North 30th Street and West Galena Street on Saturday. Cops previously spotted an unspecified human body part near North 30th Street and Lisbon Avenue Friday and a severed leg on the lakefront near Warnimont Park in Cudahy last Tuesday. Two days after the severed leg was found, Milwaukee County Sheriff’s Office detectives took a person of interest into cu…