Maybe a little charitable interpretation is warranted?
I clearly meant, post hoc rationalization for the punishment. Typically you punish when AN EXISTING law is broken. In this case, OP is arguing for new punishment based on new laws that were broken in the past.
>My guess, it was already illegal to poison the environment
No. The devil is in the definition of 'poison the environment'. We have coal plants that 'poison the environment'. We have solar panels, that through manufacturing, maintenance and decommissioning, 'poison the environment'.
>Corporations are not people. You can punish a corporation without any of that considerations.
Who owns corporations? This "corporations are not people" is such a cliché. All the rights that corporations have stem from the rights of the owners. Corporations have rights, because the owners have rights.
And who says the corporations are solely responsible? An unincorporated contractor may be responsible as well.