 HISTORY
  H9172/68-70--OPR-480, A 6X6X6 FT. CONCRETE CLUMP HUNG AT 62 FT. CLEARED TO    
  59 FT., DIVER VERIFICATION.
  H10917/00-- OPR-D392-WH;  CONTACT FOUND DURING MAINSCHEME HYDROGRAPHY IN LAT. 38-50-00.11N, LONG. 75-04-42.26W. ECHOSOUNDER DEVEL