In Norristown some firefighters were hurt (I think maybe even killed, don't remember) when a place like this caused an electrical fire.
They don't have the initiative in Norristown to dig a whole underground facility, they just convert a house in the middle of a crowded block.
Not hard to imagine how something like this could cause a massive electrical fire!
In my world, these places are legal and thus made above ground and safe, and the resources that go into five years of investigation are turned towards violent organized crime and the War on Terror.