The owner or operator of a landfill must maintain the following items in the operating record required under Sec. 264.73:
(a) On a map, the exact location and dimensions, including depth, of each cell with respect to permanently surveyed benchmarks; and
(b) The contents of each cell and the approximate location of each hazardous waste type within each cell. [47 FR 32365, July 26, 1982, as amended at 50 FR 4514, Jan. 31, 1985]