Calling the utility company is a good safety step, but honestly that feels like waiting in line at the DMV. If it were my yard and the scanner lit up, I'd be marking the spot and getting a shovel. Sometimes you just have to see what's down there. Barbara's point about old maps is smart for context, but the scanner already gave you the context. Those weird blobs could be a rusted-out toolbox or a piece of farm equipment, not always a pipe. Metal gives a much sharper hit than a buried cable.