Cluster bomb units.  These split into many smaller bomblets and cover a wide area.

Much of the bomb loading was done in the evening so the aircraft would be ready for the morning launch.  On most days there were two launches, one morning and one afternoon.

And a secondary reason much of the loading was done in the evening  was that it was much cooler than in the heat of the day for the workers.

Break time!  Even in the evening it was very hot.  Salt tablets were mandatory, dispensers located in the chow hall.