location of Bolt holes

[WallShadow]

One type of site that might make a great cover for a bolthole could be a Superfund site loaded with toxic chemicals.
Wait, you say: why would Morrow want to store things in a hazardous environment?
Because, thanks to regular salting of the samples taken by the EPA, the sites would always come up with high levels of toxins, masking the true cleaned-up status of the land--thanks to Morrow fusion and Morrow lasers and Morrow Biofiltration/bioconcentration projects. (Side note: Mushrooms, shellfish, and bamboo have proven to absorb large amounts of toxins and even radioactive particles: some even thrive in a radioactive environment.) And the owners of the ground would be a string of Morrow Corp fronts, handing it off from one "bravely struggling/bravely failing reclamation company" to another, always just managing to keep the status quo, all the effort managing to prevent the leakage into the water table.