So, the only material in enough volume to give such a huge bang (and one with a history of explosions) is the ammonium nitrate stored in the ‘fertilizer plant west of office’.
So how are they receiving this material?
Options:
1: There appears to be a rail spur running just to the west of the building.
2: They could be trucking it in.
That many tons, especially with such a small crew (only 8?), it had better be automated.
How are they off loading this material?
Can we see any kit? That may give us a clue.
How are they selling it?
We are talking volume shipments to farmers.