
 HISTORY
  UNKNOWN SOURCE--SUBM OBSTRUCTION FIRST APPEARED ON 1973 EDITION ì
OF CHART 11317 POSITION SCALED FROM CHART 11317 (1:50,000). ì
POSITION: LAT 28-36-17N, LONG 96-36-51W. (ENT GM 12/87)
  H10411/91-92-- OPR-K228-AHP; 0.7 METER DIA. STEEL PIP