I worked at Skeena Cellulose (Watson Island) Prince Rupert in non-operational management for almost 10 years before realizing it was economically doomed. One of the best decisions I ever made was to get out of Dodge before the whole thing came crashing down. And yes, it was a mess, being an elderly but large kraft mill.
Of interest, we figured the plant, bought for virtually nothing out of insolvency by our company, required about $850m to become economic (that's a lot of wampum 33 years back). We spent about $250m over 7 years from 1988 to 1995 about $100m of which was pure environmental projects. We were proud of those projects, they hugely improved water and air emissions, but there's no denying that it was money which could have been used to modernize the plant instead.
You'd never be allowed to make that call, but ironically, a thriving plant may have been over time more able to earn the profits to remediate the site, which was built atop an even older pulpmill built just after WWII ended. The original pulpmill (a much dirtier process) was built at Watson Island because it had a deep sea dock and rail access where the Allies built a munitions storage dump for the Aleutian campaign.
You want to talk about a true environmental disaster? That site had so much installed asbestos (we used to spend $3-5m/yr., again real money 33 years ago, on contractors to hoard and safely remove, there's a storage facility at the back of the island where everything is stored in sealed coffins). The old plant had abandoned transformers filled with PCB laceed coolant oil. And there were untold amounts of dioxins, which weren't known to be dangerous till the 1970s, in the effluent ponds that led straight into the ocean untreated.
Hobbes's choice, let the mill continue to pollute so that it can slowly but incrementally improve environmental compliance or put the regs to them and hope that it doesn't drive them to shutdown before more of the mess is cleaned up. Hard choices. It didn't work out for Prince Rupert thst went into a multi-decade depression when 850 extremely well paid jobs went the way of the Dodo.